YOUTH VOICE: Drying Out — Climate Change & Human Water Usage in the Murray-Darling Basin

Posted on October 5, 2010 by


BY HOLLY PERRYMAN.

Australia’s growth as a country and climate change effects on the Murray-Darling Basin have caused its water supply to decrease over the last few decades. Although it is widely believed, climate change is not the ultimate cause of the Basin’s drying crisis. It is indeed a key factor in the end result which we are now faced with, but not the only factor involved, and certainly not the biggest. For the past 200 years Australia has been growing as a country and establishing its place in the world through a growing economy and increasing population. These may be good things, but the growth of Australia as a country depends strongly on the water as a base point taken from the Murray-Darling Basin, which is now running low on its supplies.

The Murray-Darling Basin is under great stress due to the drying environment. The article “Drier Murray-Darling Basin? Get used to it” written by Wayne Meyer, Professor of Natural Resources at the University of Adelaide tells of some of the effects climate change is causing on the Murray-Darling Basin. It explains that the climate change is causing a hotter, and dryer environment is causing the amount of ground surface water moving to the top layers of soil to decrease [1].  These layers of dryer soil will take years of “above long-term average rainfall” to restore them to their natural balance [1]. The past nine years have already experienced a 200 km3 loss of water. This massive and increasing loss is putting stress onto the Murray-Darling Basin water system, affecting the general drying of catchments, decreasing amounts of groundwater, reduced run-off from the catchment areas, reduced flows in the rivers and streams and many more [1]. All the effect seen can have long-term side effects that could take years to repair and will most likely hurt all of Australia economically and environmentally.

Sustainability will be largely affected with the drying Murray-Darling Basin. Agriculture is the biggest consumer of the water taken from the Basin [2]. Through their production of foods and fibre for import and export they also provide a large benefit for Australia’s economy. With the Murray-Darling Basin Authority developing a “Basin Plan”, with the State and Commonwealth Governments agreeing on a “National Water Initiative” [2] the agriculture industry could possibly feel the largest impact of climate change drying out the Murray-Darling. It has been suggested that the cap of water usage needs to be increased by 40% to return the water to environment that has been taken and “to achieve a level of two-thirds natural flow in all the catchments of the Basin” [2]. So how can we be sure that climate change is the cause?

“South Eastern Australian Climate initiative” states that, although further research is needed to confirm, an initial analysis suggests that a one degree Celsius increase in temperature could account for the 15% of stream flow reduction that has occurred over the last 50 years. [3] Recordings confirm that across south-eastern Australia average temperatures have been increasing in the recent decades [3]. Hotter and dryer temperatures will lead to increased evaporation from the Murray-Darling Basin [3] and less humidity in the atmosphere will affect the rainfall around the area negatively. All the collected evidence from experiments conducted with global climate models strongly suggests that climate change is indeed the main cause of the Murray-Darling Basin crisis.

Although climate change is certainly a major factor in its drying, the increasing demand for the water harnessed from the Basin is most likely a key cause in its reduction and drying over the past decades. “Pipes and Drains, Rabbits and Hats, Politicians and Promises” by Lin Crase explains how the unsteady flow of the Murray-Darling Basin means it would have to be double its current size to provide the security most other dams in the world provide.  The unpredictable flows of the Basin immediately cause any industry that relies on water from it to be at continuous risk and a constant significant economic disadvantage [4]. The demand for that water has increases majorly over the past 200 years as Australia grew as a country causing expansion of urban populations, introduction of new crops, and much more. [5] All this development caused the increased demand for water extracted from the Murray-Darling Basin.

Constant increasing amount of water being taken from the Murray-Darling Basin combined with climate change causing the south eastern Australian climate to become hotter and less humid, which in turn leads to the drying of the Basin, are the combined factors that have resulted in the Murray-Darling Basin crisis. It is unfair to claim that climate change has alone been the cause of its drying when the growing of Australia as a country clearly has a higher demand for the Basin’s water supply. Therefore it can be concluded that climate change, while being a key factor in its drying out, is not the main origin while Australia’s industries and citizens have clearly been demanding an always increasing supply from its water system. The growing demand for water as a life source and as a source for Australian industries, such as agriculture, to continue to strive and grow have been assisted in drying out and causing the Murray-Darling Basin’s crisis by the negative effects of climate change. Unless we can put into play plans to restore this natural balance, and act upon them instead of just speaking of them the Murray-Darling Basin crisis will only get worse. Actions speak louder than words, and it’s time for every individual Australian to speak up.

References:

[1]

Meyer, W 2009, Drier Murray-Darling Basin? Get used to it, accessed 28 July 2010, http://www.abc.net.au/news/stories/2009/06/09/2592756.htm

[2]

Wentworth Group of Concerned Scientists 2010, Sustainable Diversions in the Murray-Darling Basin – An analysis of options for achieving a sustainable diversion limit in the Murray-Darling Basin, accessed 22 July 2010, http://www.wentworthgroup.org/uploads/Sustainable%20Diversions%20in%20the%20Murray-Darling%20Basin.pdf

[3]

South Eastern Australian Climate Initiative (SEACI) n.d., Answering questions about climate in South Eastern Australia, accessed 28 July 2010, http://www.seaci.org/docs/factsheets/SEACI_4pp_flyer_final.pdf

[4]

Crase, L 2007, “Pipes and Drains, Rabbits and Hats, Politicians and Promises”, Connections: Farm, Food and Resource Issues, accessed 22 July 2010,   http://www.agrifood.info/connections/2007/Crase.html

[5]

Bennett, J 2005, “Managing the environmental health of the river Murray: an economic perspective”, Connections: Farm, Food and Resource Issues, Spring (October), accessed 8 September 2010, http://www.agrifood.info/connections/spring_2005/Bennett.htm

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Holly Perryman is a first year Environmental Science student at La Trobe University in the Albury-Wodonga campus. She recently graduated from St. Catherine’s School , Waverley and moved to Albury from Sydney. Her hobbies include the study of Australian reptiles and playing the electric and acoustic guitar.

The views in this story are those of the author and not necessarily those of Our Voice: Politics Albury-Wodonga.

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